1. Field of the Invention
This invention relates to a wheel suspension for vehicles, comprising for each wheel of an axle a wheel control arm, which is pivotally movable against a force exerted by a torsion bar, which extends transversely to the wheel control arm. The control arm and the torsion bar constitute an integral component, which adjacent to an apex is provided with a pivotal mounting, which together with a non-rotatably mounted portion of the torsion bar defines a pivotal axis for the control arm.
2. Description of the Prior Art
A known wheel suspension of that kind is disclosed in DE-A-31 48 388 and serves to suspend both wheels of an axle. Two control arms are associated with respective wheels and constitute longitudinal control arms, which are interconnected by the torsion bar so that the two control arms and the torsion bar, which extends transversely to the direction of travel of the vehicle, constitute a single platelike member, which is rectangular in cross-section. The torsion bar portion of that member is rigidly and non-deformably secured to the chassis or to another stationary part of the vehicle so that a torsion bar extending as far as to the center of the vehicle is functionally associated with each wheel. Because the member is platelike, the control arms for the two wheels have a relatively low bending strength and they must be connected and stiffened by a beam which extends transversely to the direction of travel of the vehicle. Such beam will obviously add to the structural expenditure and weight of the suspension. Another disadvantage resides in that each of the torsion bar portions which are associated with respective wheel control arms can have only a limited length as that portion may extend in any case only as far as to the center of the vehicle, where the torsion bar is secured to the chassis or to another stationary part of the vehicle. Finally, the known wheel suspension can be provided only with longitudinal control arms and the portions consisting each of a wheel control arm and a portion of the torsion bar cannot be arranged in a freely selectable spatial orientation.
On the other hand, it is known from AT-B-375,601 to associate with each wheel of an axle a separate component, which consists of a wheel control arm and a orsion bar. But that known component is a composite assembly. The wheel control arm consists of a longitudinal control arm and is pivoted in a bearing sleeve, which is fixedly connected to the chassis or to another stationary part of the vehicle and which for the pivot pin of the longitudinal control arm provides two spaced apart bearings for taking up forces from the wheel. The torsion bar pin is non-rotatably keyed to the pivot pin of the longitudinal control arm and at its end that is remote from the wheel is fixed in a mounting that is non-rotatably connected to the chassis or another stationary part of the vehicle. That wheel suspension is relatively complicated and comprises a bearing sleeve providing two bearings for the pivot of the wheel control arm and comprises additional means by which the wheel control arm and the torsion bar are interconnected. Resides, certain difficulties arise in connection with the means by which the control arm is supported against the forces from the wheel because owing to reasons of design the two bearings in the bearing sleeve must be relatively closely spaced apart.
It is finally known, e.g., from DE-A-36 41 505 to combine a longitudinal control arm and a transversely extending torsion bar in a single member. But such members have been used only as stabilizers, which require the provision of a separate wheel spring for each wheel so that the structural expenditure will greatly be increased.